CCRMN is a program for calculating complex reactions of a medium-heavy nucleus with six light particles. In CCRMN, the incoming and outgoing particles can be neutrons, protons, 4He, deuterons, tritons and 3He. In CCRMN, we calculate all the reactions in the first, second, third, ..., up to tenth emitting processes. CCRMN is valid in 1--100 MeV energy region, it can give correct results for optical model quantities and all kinds of reaction cross sections in first, second, ..., up to tenth emitting processes.

The output data of CCRMN include total cross section; elastic scattering cross section and its angular distribution; total reaction (or nonelastic) cross section; radiative capture cross section; (x,x') reaction cross section and (x,x1,x2) reaction cross section, where x, x', x1 and x2 can be neutron, proton, 4He, deuteron, triton or 3He. To compare with experimental data conveniently, we also give the sum of the cross sections of all reactions that lead to the same residual nucleus, usually called as the isotope yields cross sections. These cross sections refer to activation or transmutation processes.

The CCRMN code is constructed within the framework of optical model, pre-equilibrium statistical theory based on the exciton model (with some changes by Zhang et al) and the evaporation model. In the first, second, and third emitting processes, we consider pre-equilibrium emission and evaporation; in the fourth to tenth emitting process, we consider only evaporation. For emission of composite particles, we adopted a pickup reaction mechanism introduced by Zhang et al. In the calculation of state densities for the exciton model, we accommodate the Pauli principle. All nuclear level densities required in the evaporation model are calculated by the formula of Gilbert and Cameron. The inverse reaction cross sections of the emitted particles used in statistical theory are calculated from the optical model. In CCRMN, for gamma-ray emission, in addition to the evaporation we also consider pre-equilibrium emission; and the partial widths are calculated based on the giant dipole resonance model with one or two resonances.

In the optical model calculation, we frequently adopt the phenomenological optical potential of Beccetti and Greenless (the parameters are usually given by a program for automatically searching for the optimum optical model parameters). The CCRMN code can also do microscopic optical potential calculations based on Skyrme force and the phenomenological optical potential calculation with CH89 or CH86 parameters for the neutron and proton channels.

The CCRMN code does not calculate direct reactions, but it can accept direct reaction cross sections calculated by other programs as input for six outgoing channels in the first process. First, CCRMN subtracts the input direct cross sections from the total reaction cross section and then adds them to corresponding statistical cross sections.

In CCRMN, we do not directly do the Hauser-Feshbach calculation, but it can accept the compound-nucleus elastic scattering cross section and its angular distribution calculated by other programs as input. CCRMN adds them to the shape elastic scattering cross section and its angular distribution respectively, and subtracts the input compound-nucleus elastic scattering cross section from the total reaction cross section. At the same time, we change the lower limit of the integration of excited energy in the first emitted process at the emitting channel corresponding to the incoming channel from zero to the first excited level energy.

In the optical model calculation, we use the Neumanove methods to solve the radial equation. The step length is 0.1 fm, and there are 150 step numbers in solving the radial equation. The maximum number of fractional waves in the optical model calculation is 60. The Coulomb wave functions used in the optical model are calculated by the continued fraction method.
The most important difference between CCRMN and CMUP2 is the integral method in the pre-equilibrium and evaporation calculation. In CMUP2 and many other programs, arguments in integrand are always kinetic energies of emitted particles, we have to do the inner integration corresponding to the last emitted particle at first, and do the outer integration corresponding to the first emitted particle at last. So the multifold number of the integration in pre-equilibrium and evaporation calculation is equal to the number of emitted particles. Limited by the computer running time, usually one can do fourfold integration at most, so before one can only consider up to fourth emitting process.

1. The target is a medium-heavy nucleus (A = 28-208).
2. The target element consists of only one isotope, or six isotopes at most, in which the difference of mass number of the heaviest and lightest isotope should be equal to or less than 10.
3. The incidental energies should be within 1-100 MeV, in which the maximum number of the incidental energy points is 40 in one calculation.

The running time depends on the numbers of energy points and they are distributed in what energy region. For example, the calculation of (n + 59Co) (there are 40 energy points distributed in region below 30 MeV) only requires about 5 minutes CPU at HP Station, however the same calculation for 4 energy points (30.0, 40.0, 50.0, 60.0 MeV) requires about 40.5 minutes CPU and for one energy point 100 MeV requires about 1 hour CPU at HP Station.

IAEA1347/01

The CCRMN program was installed and the sample problem was executed on the following systems:
1) DEC 3000 M300X, equipped with a Alpha architecture
processor at 175 MHz, running Digital UNIX V3.2 G (Rev 62)
2) Sun Solaris, under SunOS 5.3.
A few minutes (elapsed time) are required in both systems, to execute the sample problem provided with the package.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED: FACOM OS IV/F4; UNIX, DOS.

IAEA1347/01

The CCRMN program was installed and the sample problem was executed on the following systems:
1) DEC 3000 M300X, equipped with a Alpha architecture
processor at 175 MHz, running Digital UNIX V3.2 G (Rev62).
The DEC Fortran-77 compiler system Version 4.0 was used
to compile the source file and create the executable of
CCRMN.
2) Sun Solaris, under SunOS 5.3. The compiler FORTRAN 3.0
from SunPRO was used to compile the source file.